Bug 547591 - Add failOnWarning (-Werror like) flag to the batch compilerI20190625-1800

Mimic javac's -Werror behavior. Report warnings as warnings but if
-fainOnWarning argument is given and there are warnings return false
from Main.compile or exit with -1.
In case there are warnings and the argument is passed print "error:
warnings found and -failOnWarning specified" at the end to make it clear
to users why the build failed.

Change-Id: Id7268746ed29481a20dd6d295134dcd5db7ce437
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>

3 files changed, 66 insertions, 3 deletions

diff --git a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
index 1ccbeb201b..d4aa47bc36 100644
--- a/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
+++ b/org.eclipse.jdt.core.tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/BatchCompilerTest.java
@@ -734,6 +734,7 @@ public void test012(){
         "                       do not stop at first error, dumping class files with\n" + 
         "                       problem methods\n" + 
         "                       With \":Fatal\", all optional errors are treated as fatal\n" + 
+        "    -failOnWarning     fail compilation if there are warnings\n" +
         "    -verbose           enable verbose output\n" +
         "    -referenceInfo     compute reference info\n" +
         "    -progress          show progress (only in -log mode)\n" +
@@ -13139,4 +13140,46 @@ public void testBug531579() throws Exception {
 		"",
 		false);
 }
+
+public void testFailOnWarnings_NoWarning() {
+	this.runConformTest(
+		new String[] {
+			"X.java",
+			"/** */\n" +
+			"public class X {\n" +
+			"}",
+		},
+		"\"" + OUTPUT_DIR +  File.separator + "X.java\""
+		+ " -failOnWarning"
+		+ " -d \"" + OUTPUT_DIR + File.separator + "bin/\"",
+		"",
+		"",
+		true);
+	
+}
+
+public void testFailOnWarnings_WithWarning() {
+	this.runNegativeTest(
+		new String[] {
+			"X.java",
+			"/** */\n" +
+			"public class X {\n" +
+			"private int a;\n" +		
+			"}",
+		},
+		"\"" + OUTPUT_DIR +  File.separator + "X.java\""
+		+ " -failOnWarning"
+		+ " -d \"" + OUTPUT_DIR + File.separator + "bin/\"",
+		"",
+		"----------\n" + 
+		"1. WARNING in ---OUTPUT_DIR_PLACEHOLDER---/X.java (at line 3)\n" + 
+		"	private int a;\n" + 
+		"	            ^\n" + 
+		"The value of the field X.a is not used\n" + 
+		"----------\n" + 
+		"1 problem (1 warning)\n" + 
+		"error: warnings found and -failOnWarning specified\n" + 
+		"",
+		true);
+}
 }
diff --git a/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/Main.java b/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/Main.java
index 7a74db1569..8f18585cc7 100644
--- a/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/Main.java
+++ b/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/Main.java
@@ -984,6 +984,10 @@ public class Main implements ProblemSeverities, SuffixConstants {
 					}
 				}
 			}
+			if (this.main.failOnWarning && globalWarningsCount > 0) {
+				printErr("\n"); //$NON-NLS-1$
+				printErr(this.main.bind("compile.failOnWarning")); //$NON-NLS-1$
+			}
 			if ((this.tagBits & Logger.XML) == 0) {
 				this.printlnErr();
 			}
@@ -1424,6 +1428,7 @@ public class Main implements ProblemSeverities, SuffixConstants {
 	protected PrintWriter out;
 	public boolean proceed = true;
 	public boolean proceedOnError = false;
+	public boolean failOnWarning = false;
 	public boolean produceRefInfo = false;
 	public int currentRepetition, maxRepetition;
 	public boolean showProgress = false;
@@ -1779,6 +1784,9 @@ public boolean compile(String[] argv) {
 		if (this.systemExitWhenFinished) {
 			this.logger.flush();
 			this.logger.close();
+			if (this.failOnWarning && this.globalWarningsCount > 0) {
+				System.exit(-1);
+			}
 			System.exit(this.globalErrorsCount > 0 ? -1 : 0);
 		}
 	} catch (IllegalArgumentException e) {
@@ -1803,8 +1811,13 @@ public boolean compile(String[] argv) {
 		if (this.progress != null)
 			this.progress.done();
 	}
-	if (this.globalErrorsCount == 0 && (this.progress == null || !this.progress.isCanceled()))
-		return true;
+	if (this.progress == null || !this.progress.isCanceled()) {
+		if (this.failOnWarning && (this.globalWarningsCount > 0))
+			return false;
+		if (this.globalErrorsCount == 0)
+			return true;
+	}
+
 	return false;
 }
 
@@ -2333,6 +2346,11 @@ public void configure(String[] argv) {
 					this.proceedOnError = true;
 					continue;
 				}
+				if (currentArg.equals("-failOnWarning")) { //$NON-NLS-1$
+					mode = DEFAULT;
+					this.failOnWarning = true;
+					continue;
+				}
 				if (currentArg.equals("-time")) { //$NON-NLS-1$
 					mode = DEFAULT;
 					this.timing = TIMING_ENABLED;
diff --git a/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/messages.properties b/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/messages.properties
index c476812a1a..b4780afc74 100644
--- a/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/messages.properties
+++ b/org.eclipse.jdt.core/batch/org/eclipse/jdt/internal/compiler/batch/messages.properties
@@ -1,5 +1,5 @@
 ###############################################################################
-# Copyright (c) 2000, 2018 IBM Corporation and others.
+# Copyright (c) 2000, 2019 IBM Corporation and others.
 #
 # This program and the accompanying materials
 # are made available under the terms of the Eclipse Public License 2.0
@@ -54,6 +54,7 @@ compile.oneInfo = 1 info
 compile.severalInfos = {0} info
 compile.oneClassFileGenerated = [1 .class file generated]
 compile.severalClassFilesGenerated = [{0} .class files generated]
+compile.failOnWarning = error: warnings found and -failOnWarning specified
 
 ### configure
 configure.requiresJDK1.2orAbove = Need to use a JVM >= 1.2
@@ -317,6 +318,7 @@ misc.usage = {1} {2}\n\
 \                       do not stop at first error, dumping class files with\n\
 \                       problem methods\n\
 \                       With ":Fatal", all optional errors are treated as fatal\n\
+\    -failOnWarning     fail compilation if there are warnings\n\
 \    -verbose           enable verbose output\n\
 \    -referenceInfo     compute reference info\n\
 \    -progress          show progress (only in -log mode)\n\